Lesson 5: Acid-Base Theories

• Acids

  Substances that ionize in water to increase H+ ion concentration
• Bases

  Substances that dissociate to increase OH- ion concentration
• Brønsted-Lowry Theory

  An acid is a proton donor, a base is a proton acceptor
• Conjugate acid-base pairs

  • For every acid or base there is a conjugate pair (something that has either lost or gained a proton)
  • Conjugate acid: the substance that forms when a base accepts a proton
  • Conjugate base: the substance that forms when an acid loses a proton
• Identifying components of an equation

  Identify the acid, base, conjugate acid, and conjugate base

  
• H+ is ALWAYS donated because it is a single proton and has no neutrons
• Amphiprotic substances

  Substances that can be classified as acids and bases depending on the reaction they are involved with
• Strong acid

  100% ionization or dissociation
• Weak acid

  Only a few particles ionize
• Acid Ionization Constant (Ka)

  Ka = [H3O+] [A-] / [HA]
• At equilibrium

  Strong acid = large K, Weak acid = small K
• Anything with a negative exponent is a small K value